Washing machine



NOV. 24, 1942. (3, w DUNHAM WASHING MACHINE Filed Jan. 30, 1941 Fig.1.

Fig.3.

Fig.2.

Inventor George W. Dunham,

HIS Attornes.

Patented Nov. 24, 1942 UNITED STATES PATENT OFFICE WASHING MACHINE New York Application January 30, 194i, Serial No. 376,617 f 3 Claims. (01. 68-184) The present invention relates to washing machines of the type having a reciprocatory agitator.

The object of my invention is to provide a washing machine in which the clothes are washed by being drawn by water'currents against a rapidly reciprocating scrubbing surface. For a consideration of what I believe novel and my invention, attention is directed to the following description and the claims appended thereto.

In the accompanying drawing, Fig. 1 is a sectional elevation of a washing machine embodying my invention; Fig. 2 is a bottom plan view of the agitator; and Fig. 3 is a diagrammatic view of the driving mechanism.

Referring to the drawing, there is shown a washing machine having a tub I which is normally filled with water to the level indicated by the dotted line 2. Extending up through the bottom of the tub is a hollow post 3 having an integral flange 4 which is clamped against the bottom wall of the tub by means of a nut 5 threaded on the post. At the upper endof the post 3 is a guide bearing 6 for a vertical shaft I which, as shown in Fig. 3, is reciprocated by means of a cam 8 on a power shaft 9. Thecam cooperates with a. crosshead 9a integral with the shaft I. Preferably the shaft is reciprocated through a relatively short stroke which may be of the order of from one to two inches and at a rapid rate which may be of the order of from two hundred to three hundred reciprocations per minute.

Within the tub is an agitator having a hollow cylindrical body portion In depending around the post 3 and terminating adjacent the bottom of the tub in a downwardly and outwardly flared perforated section II. The upper end of the agitator body is fixed to the upper end of the shaft I, for example by a nut I2 enclosed by a cover I3 snapped over the upper end of the agitator. The bearing 6 accordingly serves as a guide for the upper end of the agitator. The lower end of the agitator is guided on a sleeve I4 fixed to the post 3 by means of a bearing I5 carried in a sleeve I6 integral with and depending within the agitator body. The lower end of the agitator body is closed by a wall I'I having a plurality of openings I8 therein which are closed by check valves consisting of radially extending flaps IQ of rubber or other resilient material secured at their inner ends to the under side of the wall I1 by means of a clamping ring 23. Upon downward movement of the agitator the flaps I9 are pressed upwardly into sealing engagement with the edges of the'openlngs I8. During this movement the bottom wall of the agitator accordingly acts as a piston, forcing liquid radially outward toward the side walls of the tub and'at the same time in-' ducing a downward flow around the body of the agitator. Upon upward movement of the agitator, a suction is produced below the wall II, drawing water inward through the perforated section II and forcing the outer ends of the-flaps I3 away from the openings I8. During the reciprocation of the agitator there is at all times a gen-.

erally downward circulation at the center of the tub around the agitator body and a generally radial and outward circulation at the bottom of the tub. This causes a water circulation in vertical radial planes, as indicated by the arrowsv 2I,

which results in bringing all of the clothes into contact with the agitator. While the water currents above the perforated section II of the agitator are always flowing in a generally downward direction, the water currents only flow in through the perforated section as indicated by arrow ZIa.

on the upward stroke of the agitator. During the upward stroke of the agitator, the clothes are accordingly drawn against the perforated section and held there by the force of the water currents flowing through the perforations. Since at this time the agitator is being positively moved, there will be some slippage between the clothes and the as indicated by arrow ZIb. This tends to slide the clothes ofi the perforated section so that upon the succeeding upward stroke a different portion of the clothes is brought into engagee ment with the perforated section. The high speed of reciprocation adds to the effectiveness of the washing action. The clothes, being suspended in the water, have considerable inertia and the parts out of contact with the agitator move relatively slowly. The parts in contact with the agitator, despite the slippage relative to the agitator, are reciprocated or vibrated at a much higher speed more nearly equal to the agitator speed. This results in a sinuous flexing of the fibers of the clothes which flushes dirt from the interstices.

What I claim as new and desire to secure by Letters Patent of the United States is:

-1. In a washing machine, a tub forreceiving liquid and clothes tobe washed and having a normal liquid level. a vertically reciprocable agitator in the tub having a hollow body having'its -lower end adjacent the bottom of the tub and having a perforated upper surface in the lower part of .the tub as regards said normal liquid level, check valve means in the lower end of said body arranged to prevent upward flow of liquid into said body whereby on the downstroke the agitator acts as a piston cooperating with the bottom of the tub to force liquid radially outward toward the side walls of the tub, and means for reciprocating the agitator in the tub through a stroke such that said perforated surface is maintained in said lower part of the tub as regards the normal liquid level, said reciprocation being sufliciently rapid to cause said radial currents to induce an upward flow along the side walls of the tub and an inward flow at the top of the tub from the tub sidewalls toward the agitator.

2. In a washing machine, a tub for receiving liquid and clothes to be washed and having a normal liquid level, a' vertically reciprocable agitator in the tub having a hollow body flaring downward and outward toward the bottom'of the tub and having its lowers end adjacent the bottom of the tub and having a perforated upper surface in the lower part of the tub as regards said normal liquid level, check valve means in the lower end of said body arranged to prevent upward flow of liquid into said body whereby on the downstroke the agitator acts as a Piston oooperating with the bottom of the tub to force liquid radially outward toward the side walls of the tub, and means for reciprocating the agitator in the tub through a stroke such that said perforated surface is maintained in said lower part of the tub as regards the normal liquid level, said reciprocation being sunlciently rapid to cause said radial currents to induce an upward flow along the side walls of the tub and an inward flow at the top of the tub from the tub side walls toward the agitator.

3. In a washing machine, a tub for receiving .liquid and clothes to be washed and having a normal liquid level, a vertically reciprocable agitator in the tub having a hollow body having its lower end adjacent the bottom of the tub and having a perforated upper surface in the lower part of the tub as regards said normal liquid level, check valve means in the lower end of said body arranged to prevent upward flow of liquid into said body whereby on the downstroke the agitator acts as a piston cooperating with the bottomof the tub to force liquid radially outward toward the side walls of the tub, and means for reciprocating the agitator at a high speed through a stroke relatively short compared to the height of the agitator body whereby said perforations are at all times substantially below said level, said reciprocation being sufllci'ently rapid to cause said radial currents to induce an upward flow along the side walls of the tub and an inward flow at the top of the tub from the tub side walls toward the agitator. 1

GEORGE W. DUNHAM. 

